1. Field of the Invention
The present invention relates to a method of fabricating a semiconductor device.
2. Description of the Background Art
A method of fabricating a semiconductor device is known in general.
Japanese Patent Laying-Open No. 5-6961 discloses a method of fabricating a semiconductor device (BiCMOS transistor) formed with a bipolar transistor and a field-effect transistor on the same substrate. In this conventional method of fabricating a semiconductor device (BiCMOS transistor), a step of fabricating the bipolar transistor includes a step of forming an oxide film on a surface of a base region after forming the base region. Then a step of forming a nitride film on a surface of the oxide film is performed. In this conventional method of fabricating a semiconductor device (BiCMOS transistor), when performing a step of forming a source and a drain of the field-effect transistor, the oxide film is employed as a protective film for performing ion implantation.